Line of Best Fit
In the interactive figure are random data points (in magenta). Drag points A and B to change the position of line AB so that the line "fits the data best." What is meant my "fits the data best?" This means to drag the line in such a way to make the sum of the squared deviations as small as possible.
One strategy to follow is to move point A in such a way as to make this sum as small as possible. Once you have done this, move point B in the same manner to make the sum as small as possible. Keep alternately moving points A and B until the sum can not be made any smaller.
Things to think about...
- Does your line of best fit pass through any of the data points?
- Is it possible to tell if the slope of the best fit line will be positive or negative before you start dragging the line?